This invention relates to the cleaning of surfaces. The invention has been devised in relation to the cleaning of a floor surface, or the surface of a conveyor belt, but it is believed the invention will also find utilization in the cleaning of other surfaces, e.g. wall surfaces.
One application of the invention is for the cleaning of conveyors for use in the food industry, where cleanliness and hygiene are of high importance. One technique which has been used for these reasons is that of steam cleaning in which steam is applied to the belt surface through one or more jets or nozzles. This combined with the agitating or abrading action of brush bristles on the belt leads to the achieving of a high standard of cleanliness. However, the application of steam to the belt surface has been carried out in a region separated from the region in which brush bristles act on the belt surface.
It is broadly the object of the present invention to provide an improved method and apparatus for cleaning a surface for example a floor surface or that of a conveyor belt. The particular features of the invention whereby such an improvement is achieved will be referred to hereafter.
According to one aspect of the present invention, we provide apparatus for cleaning a surface, comprising brush means including a body which carries bristles engageable with the surface; means for effecting movement of the bristles relative to the surface, to provide an agitating cleaning action thereon; said bristle-carrying body further being provided with steam delivery means for applying steam to said surface in a region thereof engaged by said bristles.
Conveniently said bristle-carrying body is a hollow body and said steam delivery means provides for steam to be passed therethrough and to emerge in the vicinity of said bristles.
Preferably said bristle-carrying body is in the form of a hollow cylinder with bristles carried on the external surface of a peripheral wall thereof, supported for rotation and drivable about its longitudinal axis so that the bristles are operable on a surface lying substantially parallel to said axis. Preferably steam is supplied to the interior of such a body and emerges through passages afforded by apertures in the peripheral wall of the body.
By such expedients, the invention ensures that steam is applied to the conveyor surface in the region in which it is engaged by the bristles rather than at a spacing from such region. Improved effectiveness in cleaning is thereby achieved, while less steam is required than if it were applied to the surface at a distance from the brush means.
Preferably said brush means is disposed within and covered by a hood which is arranged to approach the surface which is to be cleaned. Thereby steam emerging from the bristle-carrying body of the brush means at parts of the periphery thereof not facing the surface is constrained and prevented from escape into the surrounding atmosphere, and can contact the surface being cleaned within the entire area of such a hood as well as in the comparatively small part of such area where the bristles engage the surface, further to enhance the cleaning operation.
Preferably there is extraction means for removing loosened dirt, water due to condensation of the steam, etc. from the surface being cleaned. Preferably such extraction means has at least one intake at one or more boundary(s) of the hood; thereby it will prevent excess steam from escaping at such boundary(s).
Preferably the axis of the brush means extends transversely of a conveyor in relation to which the apparatus according to the invention is installed, and further preferably, in such an installation, the extraction means has intake openings at the front and rear of the hood with respect to the normal direction of movement of the conveyor belt.
One or more further cleaning devices or expedients may be provided in association with the apparatus according to the invention as above described, for example wiping members, brushes, air jets and so on may be provided in the region of the aforesaid intake opening or openings of the extraction system.
Apparatus in accordance with the invention may be mounted on a support means, e.g. a chassis structure enabling the apparatus to be moved over a surface which is required to be cleaned (for example a floor surface) while being supported at the appropriate height above such surface for the apparatus to function satisfactorily. Alternatively the apparatus can be supported by a fixed frame in the case such as a conveyor belt where the surface which is to be cleaned moves past the place where the apparatus is mounted.
Whilst it would be possible for apparatus in accordance with the invention to extend across the whole width of the belt, the apparatus may be supported by means providing for it to move transversely of the belt in order to enable an apparatus of lesser width to be able to cover the entire width of the conveyor belt by being moved transversely thereof. In use the cleaning apparatus may be moved transversely of the conveyor belt while the conveyor belt is moving, the movement of the apparatus being coordinated, manually or automatically, with the movement of the belt in order to cover substantially the entire surface thereof in use.
It would be possible for a steam generator and a suction generator for the extraction system to be mounted with the brush means, hood, and other associated components as referred to above, on a chassis to form a single unit movable over a floor surface for example. As applied to conveyor belt cleaning, steam may be delivered to the apparatus from a remotely-positioned steam generator, e.g. disposed alongside the conveyor. Similarly the extraction system may be connected to a source of suction at a remote location; both a steam generator and source of suction could be disposed in an equipment cabinet also containing an appropriate control system for controlling operation of the apparatus. Connection may be made by suitable, preferably flexible, pipes and electrical cables.